We are having imx6ul custom board with NAND boot option. Able to successfully boot, but when it comes to enumeration. USB ports are not enumerated until we have a device on one of the USB OTG ports.
We started off with iMX6UL and without any changes we designed a custom board. So custom board successfully enumerates with the dtb file. However, board with NAND we have used the imx6UL_evk_nand_gpmi_wiem.dtb. We got NAND working but not USB successfully any pointers as to what might be different.
Below is the enumeration log, where we connected a device on one of the ports as you can see devices on both ports gets enumerated. While when disconnected below log shows both devices getting deregistered.
root@imx6ulevk:~# ci_hdrc ci_hdrc.0: EHCI Host Controller
iAP_USBDev_read_thread_native ret -1
ERROR: iAP_USBDev_read_native, errno: 108 ret -1
ep0_thread_function(): EVENT DISABLE
SWITCHING TO USB HOST MODE..
Error: - USB BOARD COULD NOT BE SEci_hdrc ci_hdrc.0: new USB bus registered, assigned bus number 1
T IN HOST MODE.
ci_hdrc ci_hdrc.0: USB 2.0 started, EHCI 1.00
usb usb1: New USB device found, idVendor=1d6b, idProduct=0002
usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
usb usb1: Product: EHCI Host Controller
usb usb1: Manufacturer: Linux 4.9.11-02215-g5aba4a9 ehci_hcd
usb usb1: SerialNumber: ci_hdrc.0
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
usb 2-1: new high-speed USB device number 3 using ci_hdrc
usb 2-1: New USB device found, idVendor=xxxxx, idProduct=xxxx
usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 2-1: Product: PiUsb
usb 2-1: Manufacturer: hidden hidden
usb 2-1: SerialNumber: xxxxxxxxxxx
root@imx6ulevk:~# usb 2-1: USB disconnect, device number 3
ci_hdrc ci_hdrc.0: remove, state 4
usb usb1: USB disconnect, device number 1
ci_hdrc ci_hdrc.0: USB bus 1 deregistered
ci_hdrc ci_hdrc.0: timeout waiting for 00000800 in OTGSC
g_ffs gadget: high-speed config #1: FunctionFS + NCM
Please provide any pointer .